ATGATT. It stands for All The Gear, All The Time and is a war cry made by safety-conscious motorcyclists as they tackle a dangerous world on two wheels. But, do you really need to protect all your body parts all the time? Which body parts will you most likely injure in a motorcycle crash? The Center for Disease Control, World Health Organization, National Highway Traffic Safety Administration and Association For The Advancement Of Automotive Medicine has the answers you need. What can they tell us about motorcycle safety?

The CDC studied the 1,222,000 people who were treated in U.S. emergency rooms for non-fatal, motorcycle-related injuries between 2001 and 2008, then recorded their injuries by location on the body.

The CDC found that 30% of all non-fatal motorcycle injuries happen to the legs and feet

Next most-common were head and neck injuries, making up 22 percent of the total. Those were closely followed by “upper trunk” (i.e. chest, shoulder and back) wounds, then arms and hands, then “lower trunk” (i.e. hips and pelvis).

What the CDC information doesn’t tell us is how severe those injuries were or whether or not they were influenced by the wearing of appropriate safety gear.

Enter the AAAM study. While it set out to determine differences in injuries between young and old riders, it also tracked injuries related to helmet use. It tracked all injured motorcycle operators in the state of Maryland from 1998 to 2002, using both hospital discharge records and police reports. It also goes a little deeper than the CDC report, breaking injury locations down into nine areas — head, chest, abdomen, spine, neck, face, upper extremity, lower extremity, and external skin — and ranks them according to severity.

Distribution of Injury Severity Score (ISS) By Age and Helmet Use

As you can see in this graph, helmeted riders were shown to have a greater number of less severe injuries and a smaller number of more severe injuries.

Distribution of Injured Anatomic Region by Age Group

This graph shows the distribution of injuries and correlates with the CDC data showing that lower extremities represented the most common injury location. This table is not controlled for helmet use, unfortunately. Maryland is a helmet law state, so we can assume a high rate of helmet use though and the relatively low rate of injuries to the head, face and neck reflects that.

Injured Anatomic Region By Age and Helmet Use

But that’s what is tracked in this table, which shows the location of the most severe injury experienced by a given rider, tracking them across helmet use. What’s interesting here is that, while younger riders do show a greater occurrence of that most severe head, neck and face injuries among those who weren’t wearing helmets, the trend among older riders is the reverse. Lower extremities again make up a majority, even when we consider that these are the locations of only the single most severe injury on the rider’s body.

Rate ratios and 95% confidence intervals (CI) for death by body region among hospitalized motorcyclists

This table tracks the location of the injuries that resulted in death. Keep in mind, these were the deaths that occurred at the hospital, not at the accident site. Causes of death there were not reported in this study, but likely do include considerable instances of head trauma. Regardless, deaths-at-hospital were most commonly caused by thorax injuries, closely follow by head, then abdomen.

So far, this is good data. The CDC gives us the big picture of injury locations to riders nationwide, then the AAAM shows that data is not greatly influenced by helmet use. Let’s go more granular into the specific injuries with the information provided by the WHO.

In this study, motorcycle accident victims who wound up in the Jinnah Postgraduate Medical Centre in Karachi, Pakistan were surveyed to determine the precise nature of their injuries. Those with head injuries requiring neuro-surgery were excluded, as were those with only soft tissue damage, who didn’t break any bones.